InGaAsP multiple quantum well lasers with planar buried heterostructure prepared by metalorganic chemical vapor deposition

Planar buried heterostructure InGaAsP multiple quantum well (MQW) lasers consisting of six InGaAsP (λg =1.34 μm at room temperature) wells and five InP barriers were prepared by low-pressure metalorganic chemical vapor deposition. The threshold current was 35 mA, and the differential quantum efficiency was 45% at an emission wavelength of 1.3 μm. In the temperature range from −35 to 30 °C, the characteristic temperature was T0=57 K. No significant improvement in T0 was observed in these MQW lasers. However, stable single longitudinal mode operation could be obtained in a wide range of injection current without any mode changes. This effect was considered to be a result of gain narrowing of the MQW lasers.